Improved machine for amalgamating precious metals



4 .To all whom it'may concern):

,ifornia, ha've invented new and useful Improveclare that the followingis a full and exact description ofthe same, reference beingr had to 'the bottom, of the midd are grinding surfaces.

. for quicksilver. i This plate vis so arranged as` -to be 'stationary upon the bottom of the pan.

` under,surface of`which is '.provided. with grooves or gutters d, Fig. 6, and the upper mg-surface and for the 4the agitation of the p of the'pla'te D from the grinding-plateO, ace cording to the'condition `ot' the pulp which is plate D, the-curvatures of which, when faced grinding pl-ate, have' au opposite, direction from those of said grind UNITED STATES APATENT OFFICE COLEMAN, OF SAN FRANCISCO, CALIFORNIA.

iMPaovEn MAGL-unieron AMALGAMATING Pat-:clous METALS.

Specification formingfpart of Letters Patent No. 89,650, da'ed August 18, 1 863.

Be it known that I, EznA COLEMAN, of the city and county of San Francisco, Stateof Cal# ments inAmalgamators; and I do hereby dethe 4accpm panying drawings, and to the letters of reference marked thereon.

Figure 1 is atop view of the machine. Fig. 2 is a vertical sectional viewthrough the center. vFig. 3 represents, the under' or grinding. surface of ,the top plate. Fig. 4 represents the upper or grinding surface of the bottom plate. Fig. 5 represents the' top,.andFig. 6 lle plate', both of which A represents an amalgamatingpan, such as is in common use. V

B is the lower plate, which rests upon the bottom of the pan ,and is provided with slots or holes b through theisame to actas receptacles C vis the intermediate or grinding plate, thev surface withgrooves or gutters e, Fig. 5. n h are lugs fbr attaching plate (l tQ yokey for the purpose of rotatingthe'same. v j D is the upper plate, used for its extra grindpurpose of regulating. nlp, `and is represented as being stationary.` v

, s s are'set screws lfor regulating the distance being 'grou'nd. A

V4:ejare grooves upon the ,under surfaceof with the upper surface of the intermediate or ing-plate.

. k la are .-holes or slots through the upper Y plate, and may be'closed when the proper agitation of thepulp requires. lThe upper plate may bemade either with or without the grooves l f for revolving the intermediate or hereinbefore set forth.

or gutters yz3-or. with or without the slots or holes lac, according to the neness required :for the pulp and to the amount of agitationy which may be necessary in order for the'thorough amalgamation of the same.

s is a set-screw for Vref gulatiug the position .of the intermediate or grinding plate.v

The arrangement of gearing and shafting' grinding plate,

struction of the pan to 'which these improve- -ments are applied.

.Operation The foregoing description of my invention precludes the necessity of any 'Particular explanation as to its mode ofoperatiun,v

^ as that'will hsreadily understood by parties familiar with quartz machinery. It may, however, be well to state that. the intermediate plate or grinder C, havingtwo grinding-surfaces, will reduce the rockt'o a much finer 'pulp andI in greater quantity inproporti'onto the time .and power employed thaniy amal- "gamator now in use. plate, D, will allow the grinder C to be run at` The stationary top'- a-high speed without too much agitation of the pulp, which is a desideratum of great im;- portance. i,

I do 'not claim grinding plates of iron with grooves or gutters therein,'n or with slots vor holes through the same. .N either dol claimV any Vparticular form ot'groove or gutter.

What -I claim as my invention, and for Awhich Il desire Letters Patent-to issue, is

1. The use, in*amalgumating-pans, of a plate .with grinding-surfaces top` and, bottom, said plate revolving between 'two other plates.

V2. The use of a top plate, D,.in amalgamatin g-pans, for the purpose ofregnlating the agitation of the pnlp,'thej' whole substantially as described, and for the uses and'purposesas e e Y EzRA` COLEMAN. Witnesses:

Cans. R. Borm, e 4 yWrmmnn W. WrGGINs.

also for revolving the top plate, wh'en required, must vary according to the con- 

